Can the 270r be used with a PCI-E Extender?

Hi! I'm new to this forum, but I have a unique problem.

I started off a few years ago with a pre-built Alienware x51 computer and recently I moved all of the parts into my current case, the 270r. The issue that I have is that the motherboard was set up in a way that the graphics card was supposed to be beside it, parallel to it instead of connected normally, perpendicular to the mobo. There are ports (like the main case headers) right under where a normal graphics card would cover up, so I can't change graphics cards from the abnormally small and oddly shaped one I have now (GTX 745). I have been faced with this ever since I moved the parts into the new case. Recently, I remembered that PCI-E extenders are a thing! I thought this was the solution to all my problems. I could just buy an extender and move the card down a few slots on the back. But now, as I look inside the case, I see there's no space for the base of the PCI-E extender to screw in on the back wall which would usually be covered up by the motherboard, if mine wasn't so small.

What can I do? Are there any PCI-E extenders that will fit? Or can I mount the card vertically? In case it removes any confusion, no I can't use the mount from the Alienware case. Thanks!

An extender below may help if i understood the current issue?

https://www.hdplex.com/blog/htpc-hardware/hdplex-silicon-pcie-16-pcie-3-0-riser-card-review/